The Camp Nou outfit have fallen off the pace in the title race, as they find themselves seven points behind Madrid with 17 matches left to play in the competition.
Mascherano acknowledges that the distance between the two clubs is considerable but insists that Barca will remain focused on their games, waiting for Madrid to slip up.
"It is obvious that this is a big difference (between the two clubs), but we will fight until the end," the Argentine told reporters at a press conference.
"A draw for Madrid will put us back in the race if we win our matches."
"What we have to do is win our matches and wait for a slip up from Madrid, although this will not be easy because they have a great team."
"But we have to keep in mind that the most important thing is what we do."
The Argentina midfielder claimed there will be no bad blood between the two clubs if Madrid end up winning the title.
"If Madrid win all of their matches, we will obviously applaud and congratulate them for their great campaign," he explained.
"They will have deserved to win if that happens."
Mascherano said Wednesday's Copa del Rey semi-final second leg with Valencia will be 'a hard match' and warned his side against complacency after last week's 1-1 draw at Mestalla in the opening leg.
"We have to enter the match with a winning mentality; we must not rely on the result of the first leg," he said.